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Stable Isotopic Evidence for the Rise of Oxygen and Reorganization of the Sulfur Cycle from the ca. 2.3 Ga Duitschland Formation, South Africa
(2006-12-13)
Metasedimentary rocks from the Transvaal Supergroup, South Africa, were used in a stable isotopic study to investigate the evolution of the Earth's early atmosphere and early biogeochemical cycles. Sulfur isotopic evidence ...
DETERMINATION OF SULFUR ISOTOPE COMPOSITION IN SULFATE FROM TWO HIGH ELEVATION SNOWPITS BY MULTI-COLLECTOR THERMAL IONIZATION MASS SPECTROMETRY USING A DOUBLE SPIKE
(2005-05-12)
The variability of stable sulfur isotopes in nature provides a chemical tool for tracing the various sources of sulfur and a useful tool for understanding the sulfur cycle. It is also well established that snow and ice ...
Gold distribution in the Archean Tanzanian Craton: Evaluating the effects of intracrustal differentiation
(2013)
This study evaluates the vertical distribution of gold in the continental crust. Implementing a recently published method by Pitcairn et al. (2006a) for the chromatographic separation of gold from acid-digested rocks using ...
The role of mechanical mixing in the formation of reaction zones in subduction-related melange
(2013)
Traverses across metamorphic reaction zones at contacts between mafic rocks and ultramafic mélange matrix were analyzed in two mélange zones (Catalina Schist, Santa Catalina Island, CA, and Attic-Cycladic ...
Diffusion of Oxygen and Lithium Isotopes at a Contact between the Bushveld Complex and Metasedimentary Rock: Implications for the Timescale of Phepane Dome Diapirism
(2009)
Within the Eastern Lobe of the Bushveld Complex, the Phepane Dome is a circular structure of metasedimentary rock hypothesized to have formed as a wallrock diapir. To constrain the duration of Phepane Dome formation using ...
A Time-Series Geochemical Study of the ca. 2.5 Ga Batatal Formation in Brazil: Sulfur and Carbon Isotopic Insights into Environmental Conditions before the Great Oxidation Event
(2013)
Neoarchean metasedimentary rocks from the Batatal Formation, Brazil were studied using petrographic, elemental and stable isotopic techniques to provide a better understanding of coupling between the atmosphere-ocean system ...
THE ISOTOPIC ABUNDANCE OF CESIUM IN TRINITITE: IMPLICATIONS FOR POST-DETONATION ANALYSIS OF NUCLEAR MATERIALS
(2013)
Currently, there are few studies of post-detonation materials due to their extremely complex nature. The cesium isotopic composition of trinitite, the product of the first nuclear detonation, was determined using multi-collector ...
CONSTRAINTS ON THE DEPOSITIONAL AGES OF LESSER HIMALAYAN ROCKS IN CENTRAL NEPAL AND THEIR STRUCTURAL IMPLICATIONS
(2009)
The lack of good exposures and paucity of datable horizons in central Nepal has hindered the ability of geologists to piece together a relatively cohesive and straightforward stratigraphic succession within the Lesser ...
Highly Siderophile Elements and the Rhenium-Osmium System in Chondritic Components
(2012)
Chondritic meteorites and their components provide information about the early solar system, as well as processes that affected meteorite parent bodies post-accretion. The rare earth element (REE) abundances, highly ...
Quantitative modeling of mantle heterogeneity and structure
(2010)
Mantle-derived rocks, particularly mid-ocean ridge basalts (MORB) and intraplate ocean island basalts (OIB), provide insights into the compositional heterogeneity and first-order structural make-up of the modern mantle; ...